2.1 Literature review for analytical methodologies of aceclofenac and/or paracetamol Analytical methods for determination of aceclofenac in pharmaceutical formulations and/ or its degradation products or in presence of its metabolites in biological fluids

Zawilla and coworkers developed and validated three sensitive and reproducible methods for quantitatve determination of aceclofenac in pure form and in pharmaceutical formulation. The first method was based on the reaction between the drug via its secondary aromatic amino group and p-dimethylamino cinnamaldehyde (PDAC) in acidified methanol to give a stable coloured complex after heating at 75°C for 20 min. Absorption measurements were carried out at 665.5 nm. Beer's law was obeyed over concentration range 20–100 μg/mL. The other two methods are high performance liquid chromatography and densitometric methods by which the drug was determined in the presence of its degradation products over concentration range of 20–70 μg/mL and 1–10 μg/spot (Zawilla et al., 2002).